/*
* Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
import java.nio.ByteBuffer;
import java.util.Properties;
public class LimitDirectMemory {
private static int K = 1024;
public static void main(String [] args) throws Exception {
if (args.length < 2)
throw new RuntimeException();
boolean throwp = parseThrow(args[0]);
int size = parseSize(args[1]);
int incr = (args.length > 2 ? parseSize(args[2]) : size);
Properties p = System.getProperties();
if (p.getProperty("sun.nio.MaxDirectMemorySize") != null)
throw new RuntimeException("sun.nio.MaxDirectMemorySize defined");
ByteBuffer [] b = new ByteBuffer[K];
// Fill up most/all of the direct memory
int i = 0;
while (size >= incr) {
b[i++] = ByteBuffer.allocateDirect(incr);
size -= incr;
}
if (throwp) {
try {
b[i] = ByteBuffer.allocateDirect(incr);
throw new RuntimeException("OutOfMemoryError not thrown: "
+ incr);
} catch (OutOfMemoryError e) {
e.printStackTrace(System.out);
System.out.println("OK - Error thrown as expected ");
}
} else {
b[i] = ByteBuffer.allocateDirect(incr);
System.out.println("OK - Error not thrown");
}
}
private static boolean parseThrow(String s) {
if (s.equals("true")) return true;
if (s.equals("false")) return false;
throw new RuntimeException("Unrecognized expectation: " + s);
}
private static int parseSize(String size) throws Exception {
if (size.equals("DEFAULT"))
return (int)Runtime.getRuntime().maxMemory();
if (size.equals("DEFAULT+1"))
return (int)Runtime.getRuntime().maxMemory() + 1;
if (size.equals("DEFAULT+1M"))
return (int)Runtime.getRuntime().maxMemory() + (1 << 20);
if (size.equals("DEFAULT-1"))
return (int)Runtime.getRuntime().maxMemory() - 1;
if (size.equals("DEFAULT/2"))
return (int)Runtime.getRuntime().maxMemory() / 2;
int idx = 0, len = size.length();
int result = 1;
for (int i = 0; i < len; i++) {
if (Character.isDigit(size.charAt(i))) idx++;
else break;
}
if (idx == 0)
throw new RuntimeException("No digits detected: " + size);
result = Integer.parseInt(size.substring(0, idx));
if (idx < len) {
for (int i = idx; i < len; i++) {
switch(size.charAt(i)) {
case 'T': case 't': result *= K; // fall through
case 'G': case 'g': result *= K; // fall through
case 'M': case 'm': result *= K; // fall through
case 'K': case 'k': result *= K;
break;
default:
throw new RuntimeException("Unrecognized size: " + size);
}
}
}
return result;
}
}